Tire-pump.



H. F. IVIOLKENBUR.

TIRE PUMP.

APPLICATION FILED FEB. 29, 1916.

LQWW., Patented Dec. 5,1916

2 SHEETS-SHEET I.

@gp/gif j 14j I H. F. MOLKENBUR."

TIRE PUMP.

APPLICATION FILED FEB. 29. 191e.

l ,QYT Patented Dec. 5, 1916.

WITNESS/58 /l TTOH/VEYS Be it known that l, HENRY F. Momrnnnun,

t in

nominano-ja, 'e

narrante orne-init.

JF PUL, MENNESGTA.

Lenmar..

To all whomz't may concern ay citizen of the United States, and a res1- dent of St. Paul, inthe county oil-Ramsey and/State of Minnesota, have invented certain new and useful improvements in llire- Pumps, of which the following is a speciiication.

My invention relates to pneumatic tires such as are used on automobiles, and the main object thereof is to provide automatic means interposed between the inner tube and its casing for maintaining the air pressure within said tube, said means depending upon the resiliency of rubber for operation.

A further object is to construct the pumping means so as to be readily installed by an unslrilledperson and without any alteration to the inner tube or casing other than a small puncture in the former.

A further object is to provide the said pumping means as a unit, as an article' of manufacture, ready for installation between any make of inner tube and any make of casing or shoe.

p A. further object isto provide said pumping means in a simple and economical form requiring only the aforesaid puncture in the inner tube and a suitable adhesive for securing the said means to the inner tube.

And a further object is to provide,` when y desired, a safety valve to prevent bursting of the tires when the, contained air becomes overheated and therefore expands, as in hot weather or in racing, said vaive serving also as means for regulating the pressure 'within the tires and forming a component part of the aforesaid unit, said pump and valve tending to maintain the pressure at a idesired point without any necessity for stopping the automobile,

My invention is fully described in the following specification, of which the accompanying drawings form, a part` .in which like characters refer to like parts in each of the views, and in which z-Figrure 1 is a section taken through an automobile tire provided withmy invention, on the line 1--1 Fig. 3, and showing the parts in normal position; Fig. 2 is a similar view but showing the parts in air pumping position Fig. 3 is a section taken on the line of Fig. 2; Fig. Lis an' .enlarged fragmentary view similar to Fig. 3; Fig- 5 is a fragmentary top plan view of the detail shown in Fig. 4;-,

Specification of Letters raient.

with the inner tube removed; Fig. 6 is a section taken on the line 6-6 of Figli; Fig. 7 is a sectional view ofthepumping means detached and showing an attaching flap thereon for connection with the inner tube; Fig. 8 is a top plan view of the pumplng means detached from 'the inner tube and showing a band which 1 may employ; and Fig. 9 is a view similar to Fig. 7 but showing a corrugated outer surface for the pumping means for a reason later pointed out and the structure of the air feeding band. shown in Fig. 8.

Referring to the drawings, 10 represents an inner tube of an automobile tire and 11 the casing or shoe therefor, and between which arranged a block of rubber 12 which constitutes the pumping means or, rather, within which said pumping means are embodied and, if used, the safety valve.

The inner surface of the block 12 is provided with a materially raised portion 13 rounded and somewhat elliptical in form, 'whereas the outer surface of said block is conveXed to fit the inner surface of the casing "l1, said block beingprovided with relatively thin edges 14 which are intended to be cemented to the inne`r`tube 10 andl may, if desired, form supplemental flaps 15, Figs. 7 and 8, to increase the Marea' of cementing. l may also, if desired, employi'sfband 16 for holding the block 12 in place and which band is made with longitudinal passages, or cellular, to insure a supply of air tothe outer surface of the block 12 at its air inlet 1'? this band formation being shown at 18. Fig.' 8.`

rlhe center of the block 12 is lprovided with an incision 19 which is not apparent when the block is in normal position but which. when said block is compressed radially of the tire, opens up to form a chamber 20, Figs. 2, 3, 4 and 6, and serves to draw air inwardly through the inlet 17 a second incision 21 oiningr the inner end of said inlet and the chamber 2O to allow the air to reach the said chamber. The incision .21 forms a flap 2'2 over the inner en'd of the inlet 17 which serves as a valve for said inlet against outward passage. of air from the chamberO, and l provide a resisting plate 23 having a bead formed thereon and which lplate servessas a substantially rigid bearing for .the Hap 22 when air is contained within the chamber 20.

intentes nee. a, raie. Application. tiled February 29, 1916. Serial No. 61,209. l

2 isomer By reference to Figs. 3 and 4 it will be seen that I provide an'inclined incision- 24 in the upper or inner portion of the block 12 to permit the passage of air outwardly of the chamber 2O toward the inner tube 10 and within the latter through a puncture 25, this incision 24 forming a flap 26 which serves as a valve for the passage formed by said incision, and I provide a resisting plate 27, also beaded, upon theinner top of the block 12 in the position of the Hap 26 and between said block and the inner tube 1() where y, when the inner tube contains air under pressure, the flap 26 is normally forced outwardly of said tube to close 'the passage formed by the incision 24, thus preventing the passage of air from the inner tube to the chamber 20.

The tendency of the lblock 12 is to remain in or return to the normal position or shape shown in Fig. 1, but when the tire casing is depressed in the position of the block 12 by'the load being brought thereat, the block 12 is compressed into the form shown in Fig. 2, against its resisting ability. This serves to spread the sides of the incision 19 to form the chamber 20 and in the formation of which air is drawn inwardly through the inlet 17 into said chamber wherein it is imprisoned against outward movement through said inlet because of the flap 22 and its bearing plate 23. When the wheel revolves to carry this depressed portion of the tire casing beyond the load `sus taining point, said casing resumes its normal position, as does also the block 12, with the result that the sides of the incision` 19 again touch each other and the air which had been in the chamber 20 theretofore is perforce driven into the inner tube 10, and this pumping action occurs each time the tire is depressed in the position of the block 12. If, however, the air pressure within the inner tube is sul'iicient to prevent the depression of the casing, as above stated, there obviously is no pumping of air as the chamber 20 is not formed, but pumping begins as soon as the pressure falls within the inner tube below the ability of the resiliency of the block 12 to force air thereinto, this resiliency of the block 12 being calculated for desired pressures within the said inner tube.

As stated, the band 16 conveys air to the inlet 17, but this band is not essential as sulicient air will pass between the inner tube and the casing, and I may corrugate the outer surface of the block 12, as shown at 28 Fig. 9, to aid in the air supply and alsoto yield to friction caused by the depression of the casing 11.

When its use is desired I may employ a .safety valve consisting of a cylindrical casi 1ng'30 ported at 31 at its inner end and open at its outer end, a suitable bore being provided m the block 12 for lits reception and a iange being provided on said cylindrical cas ng to hold the latter` in place, a valve 32 being normally held against the port 31 by means of a spring 33 the tension of which is adjustable by means of a disk 34 screw threaded into the casing 30. When the pressure within the tire exceeds the resistance of the spring 33 the port 31 is opened to allow a portion of the air to escape from the tire and, when thissafety valve is used, it will be seen that no excess pressure can occur although a predetermined pressure is maintained by the pumping means.

The invention primarily consists of the pumping means operable in one direction by the depression of the tire casing and in .the other direction by the resiliency of the material of which the block 12 is formed, the actual pumping being accomplished by the alternate formation and elimination of an air chamber within said block.

While I have shown a practical embodiment of my invention, I do not limit myself to any specific details as modifications thereover ma su est themselves or become Y necessary to meet varying conditions, my only limitation being in the formation and elimination of an air pumping chamber within a block of resilient material.

Having fully described my invention, what I claim as new, and desire to secure by; Letters Patent, is

1. A pump for pneumatic tires, comprising a block of resilient material interposed between the inner tube and its casing and having an internal incision adapted to be expanded to form an air chamber when said block is compressed by tire compression and adapted to close to eliminate said chamber when said 'compression' is released, means for admitting air to said chamber from the exterior of said block, and means for leading air therefrom to said inner tube.

2. A pump for pneumatic tires, comprising a block of resilient material interposed between the inner tube and its casing and having an internal incision adapted to be expanded to form an air chamber when said block is compressed by tire compression and adapted to close to eliminate said chamber when said compression is released, means for admitting air to Said chamber from the `exterior of said block, means fol' leading air from said chamber to said inner tube, and

means for preventing backward movement of air through said air conducting u'xeans.

3. A pump for pneumatic tires, comprising a block of resilient material interposed between the inner tube and its casing and having an internal incision adapted to be expanded to form an air chamber when said block is compressed by tire con'lpression and adapted to close to eliminate said chamber when said compression is released, having a passage leading to said chamber from the Cir neer/,ear

exterior oi said block, and having a passage leading from said chamber to said inner tube, a valve in said@ rst named passage preventing outward air movement from said ihamber, and a valve in said. last named passage preventing air trem rentering said chamber from said inner tube.

Ll. A pump for pneumatic tires, comprising a block of resilient material interposed between the inner tube and its casing and having an; internal incision adapted to be eupurnderlto,ferm an air chamber when said blcclr is compressed by tire compression and adapted to close to eliminate said chamber when said compression is released,

Yaired air passage leading to said chamber and a valved passage leading from said chamber, said inner tube being punctured acent the outer end of said last named A pump for pneumatic tires, conn prising a block of, resilient material interposed between the inner tube and its casing and having an internal incision adapted to be expanded torni an air chamber when said block is compressed by tire compression and adapted to close to eliminate said chainber when said compression is released, having a passage leading 'to said chamber and having a assage leading trom said chamber, said inner tube being punctured adjacent the outer end of said last named passage, a tongue formed of the block material at the inner end of said iirst named passage and a tongue formed et said block materia-l at the outer end of said last named passage, said tongues serving as valves for the respective passages.

6. A pump for pneumatic tires, coinprising a block oit resilient material interposed between the inner tube'and its casing and having an internal incision adapted to be expanded to form an air chamber when said bloclr` is compressed in tire compression and adapted to close to eliminate said chamn ber when said compression is released, having a passage leading to said chamber and having a passage leading from said chamber, a tongue valve formed ot' they block material at the inner end of said iirst named passage, a tongue valve termed ot the block material at the outer end of said last named )assaoe said inner tube bein(r unctured adjacent the end of said last named passage, and a beaded bearing plate for each of said tongues to insure valve closure when and having an internal incision adapted to be expanded to form a chamber when said block is compressed in tire compression and to close to eliminate said chamber when said compression is released, means for admitting air to said chamber, means for leading air' from said chamber to said inner tube, means for preventing backward air movement through said conductingmeans, and a safety valve interposed between the interior of said-inner tube and the exterior thereof arranged in said block.

8. A pump for pneumatic tires, comprising a block of resilient material interposed between the inner tube and and its casing and having an internal incision adapted to be expanded to form a chamber when said block is compressed in tire vccmpression and to close to eliminate said chamber when said compression is released, means :tor admitting air to said chamber, means 'for leading air from said chamber to said inner tube, means for preventing backward air movement through said conducting means, and anair conveying band for holding said block in position and for supplying air to said chamber.

9; A pump for pneumatic tires, comprising a block of resilient material interposed between the inner tube and its casing and having an internal incision adapted to be expanded to form an air chamber whenl said block is compressed in tire compression and adapted to close to eliminate said chamber when said compression means for admitting air to said chamber, means for leading air therefrom to said inner tube, means for preventingbackward air movement through said air conducting means, and means for permitting circulation of air between said block and the interior et said casing consisting of corrugations on theouter surface of said block.

l10. As' an article of manufacture, for use in a pneumatic tire, consisting of a block of resilient material having an internal incision adapted to be expanded to form an air chamber when said block is compressed in line with said incision and adapted to close to 'eliminate said chamber when said compression Ais released, having a passage leading to said chamber and a passage leading from said chamber, a valve at the inner end oi said first named passage, and avalve at the outer end of said last named passage.

HENRY F. MOLKENBUR.

Signed in presence of the 'following witnesses:

Tnnononn H. AICHELE, EMILY ICHELE.

is released, 

